Albert haberle



Feb. 14, 1956 A. HABERLE ETAL 2,734,562

IGNITION SYSTEM FOR THE FLARE PIPE 0F GAS PRODUCERS Filed Oct. 5, 1951 3 Sheets-Sheet 1 5 Yr/renters.-

ALBERT HABERLE EUGEN KEM PER ATTORNEY Feb. 14, 1956 A. HABERLE ETAL. 2,734,562

N SYSTEM FOR THE FLARE PIPE OF GAS PRODUCERS IGNITIO 3 Sheets-Sheet 2 Filed Oct. 5, 1951 Fig.3

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ALBERT HABERLE EUGEN KEMPER TORNEY Feb. 14, 1956 A. HABERLE ETAL 4,

IGNITION SYSTEM FOR THE FLARE PIPE OF GAS PRODUCERS Filed Oct. 5, 1951 5 Sheets-Sheet 3 1 17 l T/ME IFELAY 46 I "'1 22 Z 1 I 1 i l 17 'l l f 1 1: i I 46 l Z r l 47 1 ldflrenfors: ALBERT HABERLE EUGEN KEMPER W O 1M2, 5 M

ATTORNEY IGNITIQN SYSTEM FOR THE FLARE PIPE OF GAS PRODUCERS Albert Hiiberle, Essen-Werden, and Eugen Kemper, Boehum, Germany, assignors, by mesne assignments, to Koppers Company, Inc., Pittsburgh, Pa., a corporation of Delaware Application October 5, 1951, Serial No. 249,848 3 Claims. (Cl. 158-125) This invention relates to an ignition device for igniting excess gas in the flare pipe of gas producers. In particular the invention is concerned with processes and apparatuses in which the ignition of the combustible gases escaping through a flare pipe is effected automatically in accordance with the gas pressure in the main gas pipe of the gas producer.

In the operation of gas producing plants, for example in generators for the production of heating gases and fuel gases forv heating the heating walls of chamber coke oven batteries the withdrawal of gas through the gas consumer is generally not constant. Each time, for example in a chamber coke oven battery, the change-over is made in the direction of heating in the heating pas sages, there is practically no consumption of gas during the actual change-over period. The gas generator or producer however continues to supply gas, during the whole of the change-over period, to the main gas pipe leading to the heating passages, as a result of which heavy increases of pressure are created in this pipe. The pressure may in the end increase so strongly that there is a considerable disturbance of the operation of the generator. It is therefore customary to provide in a branch pipe from the main gas pipe a blow-off device (safety valve) controlled by the pressure of the gas produced, which, upon the creation of an excessive pressure rise in the gas pressure in the main gas pipe, opens the path through a flare-pipe into the atmosphere. The excess gas then escapes through this flare pipe into the open air and is dispersed by natural air currents.

It is well known that the gas contains constituents which are partly poisonous and in part exhibit an objectionable smell, it they are allowed to'escape unchanged from the flare pipe into the open air.

The simplest manner of overcoming these difficulties consists in burning as completely as possible the gases escaping from the flare pipe so that the thereby resulting products of combustion chiefly carbon dioxide and water, can be discharged freely into the air without further trouble.

The ignition of the gases escaping through the flare pipe was effected hitherto, if at all, by simple ignition by a flame, e. g. in the form of a burning wick fed with oil which was introduced into the flare pipe from below by means of a rod. It is obvious that this method of ignition, depending as it does on the operating personnel is hardly reliable.

The object of the present invention is to provide a process and apparatus for carrying out this process whereby an automatic ignition of the gases escaping from a flare pipe can be effected as soon as the pressure-in the main gas pipe has reached such a value that a part of the gas escapes through the flare pipe.

A further object of theinvention consists in constructing the ignition device in such a way that the ignition of the gas-air mixture forming at the upper end of the flare pipe is automatically effected first when the flare pipe is completely exhausted of air through the gas flowing nited States Patent "ice in from below, thereby avoiding burning of gases inside the flare pipe below its top.

It is also an object of the invention to provide an ignition device in which the operation effecting the ignition is automatically interrupted as soon as the ignition has been eflected.

Further details of the invention will be evident from the following description and the accompanying drawings.

Fig. 1 shows a diagrammatic section of an automatically operable electric igniting device for flare pipes according to the invention,

Fig. 2 shows the ignition resistance arrangements according to Fig. 1 on an enlarged scale,

Fig. 3 shows a further form of construction of the arrangement of the ignition resistance in the flare pipe, and

Fig. 4 shows the electric switching device for the automatic ignition of the flare pipe.

The gas produced by the gas producer G, as in Koppers 1,246,114 and P. van Ackeren 1,964,546, which as explained above may for some reasons reach an undesirably high pressure, passes through a pipe 1 branching from the main gas pipe P, leading to branches B for the coke oven battery C into a safety chamber 2 which has two immersion bells 3 and 4 which depend into corresponding sealing liquids 5 and 6. The immersion bell 4 is suspended by a rod 7 from the underside of the immersion bell 3. Both immersion bells hang from a cable 8 which passes out from the safety chamber 2 at 9 and is led over the reversing rollers 10. On the end of the cable 8 that is outside the safety chamber 2 there is provided a counterpoise weight 11 which is of such a size that it holds in equilibrium the two immersion bells at a certain gas pressure in the main gas pipe and therefore at a prescribed position in the safety chamber.

The depth of immersion of the immersion bell is so chosen that so long as the gas pressure does not reach an undesirably high value, both bells remain immersed so that the gas from line 1 in chamber 2 is cut off from branch pipe 12 at atmospheric pressure. If the gas pressure in the pipe 1 increases then the hell 3 rises to such an extent that the bell 4 connected therewith is withdrawn completely from the sealing liquid 6. The gas from pipe 1 can then escape through the branch pipe 12 and the supply pipe 12a into the flare pipe 13.

The cable 8 carrying the counterpoise 11 is guided through the end of a switch lever 17, provided with an eye 16, and arranged so that it switches on an electrical time switch 13 when an abutment piece 15 secured on the cable 8 presses on the switch lever 17 at the eye 16. The electrical time switch 18 set in operation by the electrical potential supplied through the conductor 19 after the depression of the switch lever 17, closes lines 20 and 21 so that a second potential supplied by means of the conductor 20 passes through the conductor 21 to the transformer 22. This transformer is near the upper end of the flare pipe 13 on a special scaffold 23.

The flare pipe is divided at its upper end into several, preferably three, laterally and upwardly extending branch pipes 14, in each of which an ignition device 24 is provided near the upper edge thereof. The ignition device consists of a hair pin shaped comparatively thick wire of electrical resistance material. One end of the ignition resistance is connected to the transformer 22 whilst the other end is connected to and earthed through the flare pipe.

When the switch device 18 is set in operation a voltage is applied, as previously stated, from the conductor 20 through the switch device 18 and conductor 21 to the transformer 22. There it is changed so that the ignition resistances have passed therethrough a relatively very high current. They therefore become incandescent and ignite the gas-air mixture formed at the upper edge of thebranch pipes 14.

The provision of the ignition resistance in the branch pipes can be efiected in many ways. Fig. 2 shows a form of construction in which the ignition resistance is led vertically from below through the oblique bottom wall section 14a of the branch pipe 14, whilst in the form of construction according to Fig. 3 the ignition resistance is inclined obliquely upwards to the upper straight part of the branch pipe. According to Fig. 2 each branch pipe 14 has on the under side of the oblique section 14a an access opening 25 through which extends vertically up-, wards a metal pipe 26. The metal pipe 26 is provided at its lower end with a flange 27 which is connected by means of screw bolts 30 to the flange 28 of a further pipe 29 enclosing the first pipe. The pipe 29 is Welded on to the branch pipe 14a in the known manner. In the axis of the pipe 26 there extends a conductor 31 which is held insulated on the wall of the pipe 25 by means of insulating pipes 32 and clamps 33. The lower end of the conductor 31, which is made comparatively thick to provide a small resistance to current is connected to the transformer 22. To the upper end I" the conductor 31 there is connected the actual ignition resistance 24 which is also connected to the metal pipe 26. The current coming from the transformer 22 flows through the condoctor 31 and the ignition resistance 24 to the pipe cover 26 and from thence to earth. By releasing the screw bolts 30 the whole ignition unit can be removed and in the case of a defect, replaced by a new unit.

In the arrangement of the ignition resistance according to Fig. 3 the introduction of the hair pin shaped resistance wire is made through the opening 34 in the upper straight side wall part of the branch pipe 14. The ignition resistance 24 is connected through the two low ohmic resistance conductors 35 (one of which is preferably earthed) with the transformer 22.

The openings between the clamps 33 and the opening 34, it will be noted, are also open to the atmosphere for inflow of air to form an ignitable mixture with gas in the region of the ignition resistance elements 24 for ignition thereby.

The ignition of the gases escaping through the flare pipe need only be effected once at the beginning of the outflow of gas. The gas then burning away at the upper edge of the branch pipe 14 automatically ignites the following gas even if the ignition resistance is no longer in operation. The invention correspondingly provides for automatically interrupting the ignition current after a certain time, which time may be adjustable.

The gas flowing into the flare pipe from the safety chamber 2 must at the beginning of the inflow first displace the air upwardly from the flare pipe 13. As a resuit, a gas-air mixture is formed which in some cases, and particularly when it contains a certain percentage of hydrogen, is explosive. It is therefore dangerous to ignite the gases directly after the actuation of the switch lever 17.

According to the invention the switching in of the current causing the ignition resistances to glow is delayed, with respect to the time of actuation of the switch lever 17 by a period depending on the height and width of the flare pipe.

The switching device joining together the various switching operations in a suitable manner is shown diagrammatically in Fig. 4. The switch lever 17 actuated by the abutment piece 15, as soon as an undesirably high gas pressure in the main gas pipe 1 has raised the immersion hell 4 from the sealing liquid 6, switches on the switch 35'. As a result the coil 36 of the time relay 37 is energized and this closes the contact 38 after a definite time interval, whilst the flare pipe 8 and the attached pipes are COD]? pletely emptied of air through gas flowing in from below. As soon as the contact 38 has closed, the coil 39 of the time relay 40, the contact 41 of which is closed, and the coil 42 of the switch 43 receive current. Accordingly the contact 44 is closed so that the voltage supplied through the conductor 19 is applied to the transformer. The transformer changes the voltage and produces the high strength of current required for heating the ignition resistance 24, as a result of which the ignition of the outflowing gases is efiected.

In the meantime, after ignition has been effected, the time relay 40 has run down and the contact 41 is now interrupted. As a result the switch coil 42 is Without current and the switch 43 falls out. The contact 44 is again opened and the ignition current is thus interrupted.

When the gas pressure in the main gas pipe has again dropped, the abutment piece 15 of the cable 8 again moves upwards so that the spring 17a of the switch lever 17 can move downwards, whereby the contact 35 is opened. The relay coil 36 is then without current and the contact 33 opens. The original position is then resumed.

In order also to be able to effect the ignition of the outflowing gases independently of the time switch 33, an auxiliary switch conductor 45 is provided, this applying the voltage of the conductor 19 directly to the switch coil 42 through a contact 47 actuated through a pressure switch 46.

We claim:

1. Apparatus for automatic ignition of excess gas in a flare pipe for a main gas pipe feeding gas from a gas producer to a coke oven battery to underfire the same, comprising: a main gas pipe for ofE-flow of gas from a gas producer to a coke oven; a flare pipe extending upwardly to a high level above the main gas pipe and open to the atmosphere at its upper part for discharge of ex cess gas from the main gas pipe into the atmosphere; two immersion bells fixedly connected together for move ment in unison, with one bell operatively associated with said main gas pipe and being operable by the gas pressure in the main gas pipe to raise and lower the two bells in unison in response to changes in pressure of the gas in the main gas pipe, and the other bell operatively associated with said main gas pipe and opening and closing a communication between the lower part of the flare pipe and the main gas pipe in correspondence with the movement of the first bell in response to changes of gas pressure in the main gas pipe; an electrical resistance ignition device at the upper part of the flare pipe where it is open for discharge of excess gas to the atmosphere; electrical circuit means including switching means for impairing heat to said ignition device for efiiecting ignition thereby; and mechanical actuating means operatively associated with the switching means and with the two bells for operation thereby for closing the switching means and energizing the circuit means in response to a predetermined gas pressure in said main gas pipe, to set the electrical circuit means into operation to ignite the flare pipe during passage of gas therethrough from the main gas pipe by way of said other bell; characterized by said flare pipe being free of obstruction to gas flow from the upper part of the flare pipe, where it is open to discharge to the atmosphere, down to the region at which the other bell opens and closes the aforesaid communication between the flare pipe and the main gas pipe, and by said circuit means including a time delay means for delaying the time that the circuit means is set into operation after the initial actuating of the actuating means, for delaying the operation of the ignition device until a time after the entry of the gas into the flare pipe, for scavenging the same to prevent explosions therein, and said circuit means also including a separate electrical circuit including electrical time delay means for automatically interrupting the operation of the circuit means after it has imparted igniting heat to the ignition device for interruption of the ignition, after the ignition of the flare pipe has taken place.

2. Apparatus as claimed in claim 1, in which the flare pipe terminates at its open upper part in a plurality of laterally and upwardly extending branches, and in which an ignition device as aforesaid is removably mounted in projecting relation in each branch for access from outside the flare pipe through access openings in the branch walls, which access openings are also open to the atmosphere for inflow of air to form an ignitable mixture ignitable by the ignition devices in the branches.

3. Apparatus as claimed in claim 2 and further characterized by said access openings being in the undersides of the branches to be accessible from below the same, and a surrounding pipe around the lower portion of each ignition device, with the pipes and ignition devices fixedly attached to each other for removal as a unit through the access openings from the underside of the branch pipes,

said surrounding pipes being detachably connected in said access openings and being open to the atmosphere below for the aforesaid inflow of air to form the ignitable mixture for ignition by the surrounded ignition device.

References Cited in the file of this patent UNITED STATES PATENTS Jacobsen Oct. 17, 1922 Willcox Nov. 13, 1923 Norton May 19, 1936 Seeger et a1 June 27, 1939 Hammond July 6, 1943 Moorhead Oct. 1, 1946 

1. APPARATUS FOR AUTOMATIC IGNITION OF EXCESS GAS IN A FLASRE PIPE FOR A MAIN GAS PIPE FEEDING GAS FROM A GAS PRODUCER TO A COKE OVEN BATTERY TO UNDERFIRE THE SAME, COMPRISING: A MAIN GAS PIPE FOR OFF-FLOW OF GAS FROM A GAS PRODUCER TO A COKE OVEN; A FLARE PIPE AND OPEN WARDLY TO A HIGH LEVEL ABOVE THE MAIN GAS PIPE AND OPEN TO THE ATMOSPHERE AT ITS UPPER PART FOR DISCHARGE OF EXCESS GAS FROM THE MAIN GAS PIPE INTO THE ATMOSPHERE; TWO IMMERSION BELLS FIXEDLY CONNECTED TOGETHER FOR MOVEMENT IN UNISON, WITH ONE BELL OPERATIVELY ASSOCIATED WITH SAID MAIN GAS PIPE AND BEING OPERABLE BY THE GAS PRESSURE IN THE MAIN GAS PIPE TO RAISE AND LOWER THE TWO BELLS IN UNISON IN RESPONSE TO CHANGES IN PRESSURE OF THE GAS IN THE MAIN GAS PIPE, AND THE OTHER BELL OPERATIVELY ASSOCIATED WITH SAID MAIN GAS PIPE AND OPENING AND CLOSING A COMMUNICATION BETWEEN THE LOWER PART OF THE FLARE PIPE AND THE MAIN GAS PIPE IN CORRESPONDENCE WITH THE MOVEMENT OF THE FIRST BELL IN RESPONSE TO CHANGES OF GAS PRESSURE IN THE MAIN GAS PIPE; AN ELECTRICAL RESISTANCE IGNITION DEVICE AT THE UPPER PART OF THE FLARE PIPE WHERE IT IS OPEN FOR DISCHARGE OF EXCESS GAS TO THE ATMOSPHERE; ELECTRICAL CIRCUIT MEANS INCLUDING SWITCHING MEANS FOR IMPAIRING HEAT TO SAID IGNITION DEVICE FOR EFFECTION IGNITION THEREBY; AND MECHANICAL ACTUATING MEANS OPERATIVELY ASSOCIATED WITH THE SWITCHING MEANS AND WITH THE TWO BELLS FOR OPERATION THEREBY FOR CLOSING THE SWITCHING MEANS AND ENERGIZING THE CIRCUIT MEANS IN RESPONSE TO A PREDETERMINED GAS PRESSURE IN SAID MAIN GAS PIPE, TO SET THE ELECTRICAL CIRCUIT MEANS INTO OPERATION TO IGNITE THE FLARE PIPE DURING PASSAGE OF GAS THERETHROUGH FROM THE MAIN GAS PIPE BY WAY OF SAID OTHER BELL; CHARACTERIZED BY SAID FLARE PIPE BEING FREE OF OBSTRUCTION TO GAS FLOW FROM THE UPPER PART OF THE FLARE PIPE, WHERE IT IS OPEN TO DISCHARGE TO THE ATMOSPHERE, DOWN TO THE REGION AT WHICH THE OTHER BELL OPENS AND CLOSES THE AFORESAID COMMUNICATION BETWEEN THE FLARE PIPE AND THE MAIN GAS PIPE, AND BY SAID CIRCUIT MEANS INCLUDING A TIME DELAY MEANS FOR DELAYING THE TIME THAT THE CIRCUIT MEANS IS SET INTO OPERATION AFTER THE INITIAL ACTUATING OF THE ACTUATING MEANS, FOR DELAYING THE OPERATION OF TH IGNITION DEVICE UNTIL A TIME AFTER THE ENTRY OF THE GAS INTO THE FLARE PIPE, FOR SCAVENGING THE SAME TO PREVENT EXPLOSIONS THEREIN, AND SAID CIRCUIT MEANS ALSO INCLUDING A SEPARATE ELECTRICAL CIRCUIT INCLUDING ELECTRICAL TIME DELAY MEANS FOR AUTOMATICALLY INTERRUPTING THE OPERATION OF THE CIRCUIT MEANS AFTER IT HAS IMPARTED IGNITING HEAT TO THE IGNITION DEVICE FOR INTERRUPTION OF THE IGNITION, AFTER THE IGNITION OF THE FLARE PIPE HAS TAKEN PLACE. 